Method and apparatus for providing air flow

ABSTRACT

Disclosed example respirators comprise: a filter configured to filter the air; a blower fan configured to provide continuous air flow at variable speeds; an air duct configured to direct air from the blower fan to an exhaust location, the blower fan configured to blow air through the air duct; and a blower controller configured to: control the blower fan to automatically adjust an airflow speed of the blower fan to a plurality of airflow speeds over a plurality of different time periods, the plurality of airflow speeds being within an airflow speed range.

BACKGROUND

The present disclosure relates to providing air to a user, and moreparticularly, to a method and apparatus for providing air flow.

Limitations and disadvantages of conventional systems for providing airto an interior of a protective device worn by a user, such as, forexample, powered air purifying respirators, will become apparent to oneof skill in the art, through comparison of such approaches with someaspects of the present method and system set forth in the remainder ofthis disclosure with reference to the drawings.

SUMMARY

Methods and systems are provided for a method and apparatus forproviding air flow, substantially as illustrated by and described inconnection with at least one of the figures, as set forth morecompletely in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of some example embodiments,taken in conjunction with the accompanying drawings.

FIG. 1A is an drawing of an example of a blower unit providing air to ahelmet in accordance with an embodiment of the disclosure.

FIG. 1B is a drawing of an example of a blower unit providing air toclothing in accordance with an embodiment of the disclosure.

FIG. 1C is a description of aa example of a blower unit in accordancewith an embodiment of the disclosure.

FIG. 1D is a drawing of an example of a blower unit that is a part of aprotective device in accordance with an embodiment of the disclosure.

FIG. 2 is a drawing of an example of a blower unit providing air to awelding helmet in accordance with an embodiment of the disclosure.

FIG. 3A is a drawing of an example of a user interface on a blower unitfor controlling the blower unit in accordance with an embodiment of thedisclosure.

FIG. 3B is a drawing of an example of a user interface on a helmet forcontrolling a blower unit in accordance with an embodiment of thedisclosure.

FIG. 4 is an example of a flow chart for a blower unit in accordancewith an embodiment of the disclosure.

FIG. 5 is an example of a flow chart for a blower unit in accordancewith an embodiment of the disclosure.

DETAILED DESCRIPTION

Devices such as a fan for providing air can be used for variouspurposes, including cooling the user. However, if the user is wearing aprotective device such as a helmet or protective clothing, thenequipment designed for this purpose may be needed to enable the air toreach the interior of the protective device. This equipment can begenerally referred to in this disclosure as a “blower unit” where theblower unit provides air to an interior of the helmet or the protectiveclothing to cool the user. Additionally, where the air quality is notvery good because the user is in a dusty, smoky, or other undesirableenvironment, the air may need to be filtered before it is provided tothe user, especially if the air is provided to a helmet where the airwill be breathed by the user.

The filtering blower unit is also referred to as powered air purifyingrespirators (PAPR) or a respirator, and can be used in conjunction with,for example, welding helmets in environments where welding fumes can behazardous or at least irritating to welders. These systems usually comewith either a belt mounted or helmet mounted blower unit that blowspurified air inside a positive pressure enclosure to the welder via anair duct. The blower unit consists of a fan and motor that drives airthrough, for example, a high efficiency particulate air (HEPA) filter toremove harmful and unwanted particles from the air stream. The filtercan be before or after the fan.

A blower fan may support two or more speeds for the airflow delivered tothe protective device, where the user can have an option to switch amongthe available speeds. A higher speed can be more desirable to the userbecause it provides more airflow to improve thermal comfort. However, ahigher speed consumes more energy requiring more frequent replacement ofbatteries, or the user would use (and carry) a heavier battery pack.

An embodiment of the disclosure is a respirator configured to provideair to a protective device, where the respirator includes a filterconfigured to filter the air, a blower fan configured to providecontinuous air flow at variable speeds, an air duct configured to directair from the blower fan to an exhaust location, where the blower fan isconfigured to blow air through the air duct, and a blower controllerconfigured to control the blower fan to adjust an airflow speed of theblower fan within an airflow speed range according to an airflow speedpattern. The respirator can include a battery as a source of power forthe respirator.

The respirator comprises at least one sensor configured to detect atleast one environmental condition, and the blower controller isconfigured to adjust the airflow speed in response to the detectedenvironmental condition. A sensor can be a temperature sensor, where theblower controller is configured to adjust the airflow speed according tothe airflow speed pattern in response to detecting that ambienttemperature around the respirator has exceeded a temperature thresholdand/or detecting that ambient temperature in the protective device hasexceeded a temperature threshold.

A sensor can be an air quality sensor, where the blower controller isconfigured to adjust the airflow speed according to the airflow speedpattern in response to detecting that air quality around the respiratorhas fallen below a pre-determined air quality threshold and/or detectingthat air quality in the protective device has fallen below apre-determined air quality threshold.

The respirator can also comprise a communication circuit configured toreceive a signal, where the blower controller is configured to use thereceived signal to control the blower fan to adjust the airflow speed ofthe blower fan. For example, the communication circuit can receiveexternal sensor environmental information sensed by an external sensordevice external to the respirator, where the blower controller isconfigured to adjust the airflow speed according to the airflow speedpattern in response to the received external sensor environmentalinformation. The communication circuit can receive the environmentinformation wirelessly or via a wired circuit.

The respirator can be set to a different minimum airflow speedincluding, for example, 160 liters per minute (L/min) or 170 L/min. Theminimum speed may depend on where the respirator is used.

The airflow speed pattern can change the airflow speed from a firstairflow speed to a second airflow speed and then change the airflowspeed back to the first airflow speed, where the airflow speed patternis completed at least once. Increasing the airflow speed can be at afirst airflow change rate, and decreasing the airflow speed can be at asecond airflow change rate, where the first airflow change rate and/orthe second airflow change rate is a variable airflow change rate.

The respirator is configured to connect to the protective device, suchas, for example, a head worn device and a protective clothing, toprovide the air to an interior of the protective device. The respiratorcan also comprise a user interface device configured to receive inputfrom a user, where the blower controller is configured to use the inputto control the blower fan to increase the airflow speed from a lowerairflow speed to a higher airflow speed for a first period of time to afirst upper airflow speed.

Successive inputs received by the user interface device can also be usedto increase the period of time to longer periods with each successiveinput until a maximum period of time is reached. Then, the next inputcan reduce the time period to the first period of time. Variousembodiments of the disclosure can have different algorithms including,for example, reducing the time to zero to thereby bring the airflowspeed back to the lower airflow speed.

Successive inputs received by the user interface device can also be usedto increase the airflow speed from a lower airflow speed to higherairflow speeds with each successive input until a maximum upper airflowspeed is reached. Then, the next input may reduce the airflow speed tothe lower airflow speed or to the next higher airflow speed depending onthe embodiment. Various embodiments may also have separate inputs forthe time period and the airflow speed.

The respirator is also configured use the input to change the airflowspeed pattern to another airflow speed pattern, or to use the input tocontrol the blower fan to go from using an airflow speed pattern tooutput varying air flow to outputting a substantially constant air flow,or to control the blower fan to go from outputting a substantiallyconstant air flow to using the airflow speed pattern to output varyingair flow.

The blower controller is configured to control the blower fan using theairflow speed pattern by adjusting the airflow speed among a pluralityof airflow speeds, where each of the plurality of airflow speeds isassociated with a respective one of a plurality of time periods.Accordingly, the blower fan can blow at a lower airflow speed for afirst period of time and a higher airflow speed for a second period oftime, where at least one of the first period of time and the secondperiod of time is adjustable. The number of airflow speeds and periodsof times are variable depending on the implementation, and variousimplementations may allow adjustment of at least one of the airflowspeeds and/or at least one of the periods of time.

The communication circuit is configured to receive a signal, where theblower controller uses the received signal to control the blower fan toadjust the airflow speed of the blower fan. Accordingly, there may be aremote control for the respirator.

The blower controller can be configured to control the blower fan toadjust the airflow speed of the blower fan according to the airflowspeed pattern for a selected time period, and to control the blower fanto use another airflow speed pattern when the selected time period haselapsed.

Another embodiment of the disclosure is a welding helmet that includes ablower fan configured to provide continuous flow of air to an interiorof the welding helmet, a blower controller configured to control theblower fan to adjust an airflow speed of the blower fan within anairflow speed range according to an airflow speed pattern, a filter tofilter the air, and a battery configured to provide power to the weldinghelmet.

Another embodiment of the disclosure is a blower device for providingair to a protective device includes a blower fan configured to provideair flow to an interior of the protective device, a blower controllerconfigured to control the blower fan to adjust an airflow speed of theblower fan within an airflow speed range according to an airflow speedpattern, and a battery configured to provide power to the blower device.The blower device can also include a filter to filter the air and/or atleast one sensor to detect an environmental condition such as airquality, temperature, and/or humidity, where the blower controller beingconfigured to adjust the airflow speed in response to the detectedenvironmental condition. The protective device can be a device that isworn on the head such as, for example, a helmet, or worn on the bodysuch as clothing or gloves/mittens.

FIG. 1A is a drawing of an example of a blower unit providing air to ahelmet in accordance with an embodiment of the disclosure. Referring toFIG. 1A, there is shown a blower unit 100 that is able to provide air toan interior of the helmet 104 via the tube (or air duct) 102. Someembodiments may not include a filter for the blower unit 100. Whether ablower unit 100 has a filter can depend on the use of the blower unit100 and the environment it is meant to be used in. For example, a blowerunit 100 for welding could have a filter.

FIG. 1B is a drawing of an example of a blower unit providing air toclothing in accordance with an embodiment of the disclosure. Referringto FIG. 1B, there is shown a blower unit 100 that is able to provide airto the clothing 106 via the tube (or air duct) 102. Some embodiments maynot include a filter for the blower unit 100. Whether a blower unit 100has a filter can depend on the use of the blower unit 100 and theenvironment it is used in. For example, if the clothing 106 includes ahelmet, or if the clothing 106 is used where hazardous material candamage a person due to exposure, the blower unit 100 would have afilter. Whether a blower unit 100 includes a filter is implementationdependent, and the blower unit 100 may have an option for a filter toallow the user to make a choice.

FIG. 1C is a description of an example of a blower unit in accordancewith an embodiment of the disclosure. Referring to FIG. 1C, there isshown the blower unit 100 with a blower controller 110, memory 112, userinterface 114, communication interface 116, filter 118, a blower fan120, and a battery 130. The blower controller 110 can comprise hardwareand/or software (also firmware) that can controller the various parts ofthe blower unit 100. The software can be stored in the memory 112, wherethe memory 112 comprises non-volatile memory, volatile memory, and/orother mass storage device. The mass storage device can be, for example,a hard drive. The memory 112 can also store other information such as,for example, airflow speed pattern, minimum and maximum airflow speeds(rates) for different uses (use in EU, USA), etc. The airflow speedpattern can comprise the airflow speed for different modes of blowerunit 100 operation and the durations for the different airflow speeds.

The blower controller 110 can control the speed of the blower fan 120,receive inputs and output messages via the user interface 114,communicate with other devices via the communications interface 116,enable use of the filter 118 if such an option is available, and/orcontrol power supplied by the battery 130.

The user interface 114 can comprise, for example, input devices such asbuttons that can be pushed and/or rotated, number pads, arrow pads,keyboard, mouse, etc. The user interface 114 can also be a display(LED/LCD text/graphics/video display, LED lights, etc.) where statusand/or messages can be displayed. The user interface 114 can alsocomprise a touch sensitive screen, and the touch sensitive screen mayalso be able to display text, graphics, and/or video.

The communication interface 116 can comprise hardware and/or softwarethat can be used to exchange information with other devices via wirelessor wired communication. The communication can be via protocols such as,for example, WiFi, Bluetooth, USB, etc. Some of the information that canbe received by the blower unit 100 can be environmental informationmeasured by devices external to the blower unit 100. This informationcan be used by the blower controller 110 to determine, for example, theairflow speed for the blower fan 120, various airflow speed patterns,etc. An airflow speed pattern can have the blower fan 120 operate atdifferent speeds, where each speed is for a certain corresponding amountof time. For example, one airflow speed pattern can have the blower fan120 blow at a first airflow speed for a first period of time and thenfor a second airflow speed for a second period of time. This cycle maythen repeat continuously. The first airflow speed and the second airflowspeed will be different, but the first period of time and the secondperiod of time can be different or the same.

In some situations, the filter 118 may be needed to filter the air. Thefiltering can comprise removing particulates, as well as scrubbingdifferent gases, humidity, and/or odors from the air. This can allow theuser to enjoy a better air quality when the air is blown in to theuser's protective device, especially if the protective device is a headworn device such as a helmet. Even when air is blown in to a non-headworn device, filtering particulates from the air can be appropriate tokeep the clothes under the protective device cleaner than if the air wasunfiltered.

Some embodiments might not include the filter 118 if that embodiment isto be used for cooling a user and is not expected to be in anenvironment with poor air quality. Other embodiments can include afilter 118 such as a HEPA filter, a carbon filter, an electrostaticfilter, and/or any other types of appropriate filters. The filter 118may be placed or removed, and the filter 118 may be replaced with afilter 118 of a different type. For example, the filter 118 can be aHEPA filter that can be replaced with a carbon filter. The blower fan120 acts to move air, and can use any type of appropriate technologysuch as, for example, bladed fans or bladeless fans.

There is also a hardware logic block 122 for the general miscellaneouslogic that may be present in any hardware device. The hardware logicblock 122 can include, for example, timers that can be set to interruptthe blower controller 110 upon expiration of time.

The sensor block 124 can comprise one or more sensors that senseenvironmental conditions such as, for example, temperature, humidity,smoke, dust, etc. These environmental conditions can be used todetermine the airflow speed and/or the airflow speed pattern. Theenvironmental conditions may also be used to filter the air for thoseembodiments that are able to turn on and off filtering of air. Thesesensors in the sensor block 124 may be in the blower unit 100, on theoutside of the blower unit 100, or remote sensor(s) that communicate tothe blower unit 100. The blower unit 100 may also receive sensor signalsfrom other sensors that are not part of the sensor block 124. Forexample, these other sensors can be part of the protective device.

The battery 130 provides power for the blower unit 100. Some embodimentscan have the battery 130 separated from the rest of the blower unit 100,while other embodiments can have the battery 130 as part of the blowerunit 100.

FIG. 1D is a drawing of an example of a blower unit that is a part of aprotective device in accordance with an embodiment of the disclosure.Referring to FIG. 1D, there is shown a blower unit 160 that is a part ofthe protective device 150. If the protective device 150 is a weldinghelmet, the blower unit 160 would not need to be connected to thewelding helmet by an air duct.

FIG. 2 is a block diagram of an example of a blower unit providing airto a welding helmet in accordance with an embodiment of the disclosure.Referring to FIG. 2 , there is shown a welding system 200 connected tothe blower unit 100 providing air to an interior of the welding helmet270 in accordance with an embodiment of the disclosure. The weldingsystem 200 includes a power source 240 that converts input power to ACand/or DC power suitable for use in welding operations. The power source240 includes a power converter 246 that converts input power 248 toeither AC and/or DC welding power for output to a torch 280 connected topower outputs 242, 243. In the example of FIG. 2 , the welding system200 is connected to the torch 280 via the power output 242 and to thework clamp 282 via the power output 243 to form an electrical circuitwith a workpiece 284 when an electrical arc is started.

The power source 240 includes a controller 256 that is operativelycoupled to the power converter 246. The controller 256 may also bereferred to as a welding processor. The controller 256 may beimplemented using one or more of logic circuits, general-purposemicroprocessors, special-purpose microprocessors, application-specificintegrated circuits (ASIC), field programmable gate arrays (FPGA)s,digital signal processors (DSPs), and/or any other type of logic and/orprocessing device. For example, the controller 256 may include one ormore digital signal processors (DSPs). Alternatively, the controller 256could include discrete component control circuitry to perform controlfunctions. The controller 256 controls the output power from powerconverter 246 by generating control signals 257 to control switchingcomponents (e.g., the SCRs) in power converter 246. The controller 256may also generally control operation of the welding system 200.

The controller 256 receives user-selected operating parameters from theuser interface 244. The controller 256 also transmits to the userinterface 244 information about the welding operation that is valuableto the welder, including arc voltage, arc amperage, and/or preferredselector settings. The example user interface 244 can include any typeof interface device, such as a keyboard, a pointing device (e.g., amouse, a trackpad), a microphone, a camera (e.g., gesture-based input),a touch sensitive screen, and/or any other type of user input and/oroutput device.

The controller 256 can also be configured to control various aspects ofthe welding system 200. For example, the controller 256 can controlinput and output via the user interface 44 and/or the communicationsinterface 245. As described above, the controller 256 can genericallyrefer to a plurality of devices, including processors, which work inconcert to control various aspects of the welding system 200.

In some examples, the welding system 200 can be configured tocommunicate via the communication interface 245 using a wired and/orwireless communication from another device. The communication can be,for example, the welding system 200 transmitting various environmentalmeasurements sensed by the sensors 247 to the blower unit 100 and/or thewelding helmet 270. The sensors 247 may be able to measure, for example,temperature, humidity, air quality, etc.

A memory device 258 and a storage device 260 are coupled to thecontroller 256 for storing data including the settings of the selectorson user interface 244 for future retrieval after power-down and/orbetween welding cycles. The memory device 258 can include a volatilememory, such as random access memory (RAM) 258 b, and/or a nonvolatilememory, such as read-only memory (ROM) 258 a. The storage device 260 caninclude magnetic media such as a hard disk, solid state storage, opticalmedia, and/or any other short and/or long term storage device. Thememory device 258 and/or the storage device 260 can store information(e.g., data) for any purpose and/or transmit stored data upon request bythe controller 256. For example, the memory device 258 and/or thestorage device 260 may store processor executable instructions (e.g.,firmware or software) for the controller 256 to execute.

The memory device 258 can store a variety of information and can be usedfor various purposes. For example, the memory device 258 can storeprocessor executable instructions (e.g., firmware or software) for thecontroller 256 to execute. The stored information may also comprise, forexample, information regarding airflow patterns and speeds.

There is also a hardware logic block 250 for the general miscellaneouslogic that may be present in any hardware device. The hardware logicblock 250 may include, for example, timers that can be set to interruptthe controller 256 upon expiration of time.

The air flow speed from the blower unit 100 can be constant for a timeor the air flow speed can vary depending on various conditions of theenvironment, and also under control of a welder. For example, the weldermay control the blower unit to blow at a different constant speed, atspeeds that vary over time, or at a different speed(s) for a period oftime before going back to the original speed. The air flow speed canchange due to environmental conditions such as temperature, humidity,air quality, etc. that can be detected by one or more sensors in thesensor block 124 in the blower unit 100 or the sensors 247 in thewelding system 200. Various embodiments of the disclosure can receivethe environmental condition information via, for example, thecommunication interface 116.

Accordingly, the cycling of air at two airflow settings creates abreathable pocket for the user above atmospheric pressure at all timesand more effectively refresh the users. The blower unit 100 providesfiltered air by filtering undesirable substances from weldingenvironments at a flow rate at or above 170 L/min in the United Statesand at least 160 L/min in the European Union. Appropriate standards willbe met by those embodiments designed for operation in other foreigncountries.

When the user selects the intermittent airflow mode the fan speedcontrols will blow air with, for example, a lower airflow speed of 175L/min for a period of time and a higher airflow speed of 200 L/min foranother period of time at a certain frequency. Furthermore the dutycycles for the low/high airflow speeds could be symmetric or asymmetric.These variables described can be set by the manufacturer and/orcustomized by end users.

For reduced power consumption the rate and frequency of the oscillationcan be adjusted to maximize fan efficiency to minimize powerconsumption. The welder has to carry the weight of the battery systemand it is generally desirable to minimize this weight because it cancreate neck and back fatigue with prolonged use. A reduction in powerconsumption could be achieved by taking into account the current drawrequired for the motor to maintain a certain fan speed. A quickerincrease in airflow speed would require a larger current draw than amore gradual increase. Thus the frequency and rate of intermittentairflow can be adjusted to take advantage of this to minimize powerconsumption. Similarly, as the airflow goes from its higher speed to itslower speed, the fan speed can be reduced by letting it naturally decayfrom the higher airflow speed to the lower airflow speed.

As stated, PAPR systems used in welding applications in the US arerequired to be above 170 L/min. Accordingly, a factor of safety (chosenby manufacturer or customized by end user) can also be applied and toprevent the blower unit (respirator) 100 from going below, for example,175 L/min. Alternatively, these parameters could be automatically setthrough wireless communication to a sensor input such as temperature,humidity, or air quality measurement. The information obtained fromthese sensors could be inputted into a pre-configured algorithm that candetermine the intermittent airflow parameters and/or turbo airflow modeparameters. Based on sensor inputs an algorithm could also automaticallydetermine when to trigger and turn-off these modes.

It should be noted that these are only some examples of different sensortypes and the disclosure is not limited to these particular sensor typeswhen relating adjustable variables on the intermittent and turbo airflowmodes on the PAPR system. For example, the system could also take inputfrom the PAPR blower system to detect filter clogs or other systemrestrictions and modify the airflow speeds accordingly within the limitsof the motor. If the “turbo” and intermittent airflow modes are notpossible to be used safely within the requirements of a PAPR variousembodiments of the system could provide a visual, auditory, or vibrationwarning to the user.

Alternate embodiments could include an input signal from a temperaturesensor located externally to the blower unit or welding helmet that canwirelessly activate either an “intermittent” or “burst” mode of airflow.The input signal isn't limited to a sensor. Various controls of theblower unit 100 may be activated by a person or device remote to theblower unit 100.

With an embodiment of the disclosure, a welder can customize the patternof intermittent air flow or burst of high velocity air flow by using,for example, the user interface 114. A user may be able to adjustparameters such as frequency of air flow variation or length of burstmode. Although various descriptions have been given for a PAPR systemused with a welding helmet, the blower unit 100 can be used with anyhead worn protective respirator used in an industrial weldingenvironment such as hard hats and grinding face shields, for example.The blower unit 100 can also be used with users of other protectivedevices such as, for example, other head worn devices and protectiveclothing. As described, the blower unit 100 can be integrated in a headworn protective device or other protective devices/clothing.

The blower unit 100 can also be adapted for use in a using athermoelectric cooling device, with or without the filter 118. This caninclude any system where highly compressed air is released on one sideof the thermoelectric device or a heat sink fin to cool the air thatcomes into contact with the other side those devices. The “turbo” modefor example could be linked with the release of this highly compressedair so that as air blows on to the heat sink or thermoelectric device itprovides a short burst of cool air. Various embodiments can also be usedwith an air system that provides clean breathable air with filtered airmoving through an air compressor. A digital automatic pressure regulatormay be used to create the intermittent air flow.

FIG. 3A is a drawing of an example of a user interface on a blower forcontrolling the blower in accordance with an embodiment of thedisclosure. Referring to FIG. 3A, there is shown the user interface 300for the blower unit 100 with a power button 302 and an airflow button305. The power button 302 can be used to turn a blower unit on and off.The airflow button 305 can be pressed, for example, to step through thedifferent airflow modes. The airflow modes can be, for example, one ormore airflow speeds, with each airflow speed on for a set period oftime. There may be, for example, three different airflow modes — normal,intermittent, and turbo.

The normal mode can be a constant airflow at a certain airflow speed.The intermittent mode may cycle between two airflow speeds, with eachairflow speed set for a corresponding period of time. In theintermittent mode, the airflow speed can vary from the first airflowspeed to the second airflow speed then back to the first airflow speed.This can continue until the blower unit is turned off or switched toanother mode. The turbo mode may be a mode where the blower unitincreases the airflow speed for a certain period of time.

Various embodiments can allow changing the airflow speed(s) and/or theperiods of time for the intermittent mode and/or the turbo mode. While aspecific user interface was described for user input, variousembodiments can use other user interfaces such as touch sensitivedisplays, rotary knobs, rocker switches, etc. Also, while not shown,there may be a separate button to activate the turbo mode.

FIG. 3B is a drawing of an example of a user interface on a helmet forcontrolling a blower unit in accordance with an embodiment of thedisclosure. Referring to FIG. 3B, there is shown helmet user interfacewith a button 325 that controls the blower unit to enter the turbo modeas described with respect to FIG. 3A. Accordingly, the user may push ortap the button 325 for a blast of air for a period of time when he feelsthe need for additional air. The period of time for the turbo mode maybe adjustable for various embodiments.

Various embodiments may also have more than two airflow speeds.Accordingly, each tap of, for example, the button 325 may allow theturbo mode to go to successively higher airflow speeds until a maximumairflow speed is reached. The next tap of the button 325 may then bringthe airflow speed to the lowest airflow speed. Another embodiment of thedisclosure may bring the airflow speed from the maximum airflow speed tothe first airflow speed above the lowest airflow speed.

Additionally, each tap of, for example, the button 325 may allow theturbo mode to go to successively to longer periods of time until amaximum period of time is reached. The next tap of the button 325 maythen bring the period of time to the first (smallest) period of time.Various embodiments of the disclosure can have different algorithmsincluding, for example, reducing the time from maximum to zero tothereby end the turbo mode to bring the airflow speed back to the lowestairflow speed.

Still other embodiments may allow changing the airflow speeds and theperiods of time.

FIG. 4 is an example of a flow chart for a blower unit in accordancewith an embodiment of the disclosure. Referring to FIG. 4 , referencesto devices described in the previous figures will be made forconvenience of description. At 402, the blower unit 100 may be poweredon and in a state of providing continuous airflow at a constant firstairflow speed. Depending on the usage of the blower unit 100, theairflow may be continuous at a minimum airflow speed to meet regulatoryrequirements. For example, presently, in the United States a respiratorshould have a minimum airflow speed of 170 L/min and 160 L/min in theEuropean Union. At 404, the blower controller 110 may check to see if anintermittent mode may be requested. If not, the blower unit 100 may stayat the constant first airflow speed. If intermittent mode has beenrequested, the blower unit 100 initiates intermittent mode at 406 usingthe first airflow speed and a second airflow speed according to theairflow speed pattern that is in use.

At 408, the blower unit 100 will control the blower fan 120 to anappropriate second airflow speed. It should be noted that at 408, theblower controller 110 switches the blower fan 120 to operate at thesecond airflow speed if it is presently operating at the first airflowspeed, and vice versa. After the blower fan has been operating for thesecond airflow speed for a corresponding period of time indicated in theairflow speed pattern, the blower controller 110 checks at 410 whetherto exit the intermittent mode. If so, the blower controller 110 sets theblower fan 120 to blow at the constant first airflow speed at 412 andthe blower unit 100 returns to 402.

If the blower unit 100 is to remain in the intermittent mode, the otherairflow speed is set for the blower fan 120 at 408, and the flow chartoperations continue.

While FIG. 4 shows explicit stages for an example flowchart, otherembodiments can use different stages or different methodology. Forexample, the flowchart of FIG. 4 may be performed with softwareinstructions, or the control may also be done using a hardware statemachine in the hardware logic block 122 or 250, or some combination ofhardware state machine and software control may be used. A timer mayalso be used for some functionality such as, for example, waiting forthe appropriate time periods before switching from the first airflowspeed to the second airflow speed, and from the second airflow speed tothe first airflow speed. The expiration of time may be indicated by anumber of different methods. For example, expiration of time may triggeran interrupt, a flag may be set, a hardware signal may be set, etc.

Additionally, while two different airflow speeds were given as examples,various embodiments need not be so limited. The number of airflow speedsand the switching from one airflow speed to another are implementationdependent.

FIG. 5 is an example of a flow chart for a blower unit in accordancewith an embodiment of the disclosure. Referring to FIG. 5 , referencesto devices described in the previous figures will be made forconvenience of description. The blower unit 100 may be in a run state at502, where the blower unit 100 is running in a selected mode. The blowerunit 100 may start, for example, when the power button 302 is pressedand may run at 502. The blower unit 100 may start in a default state ofconstant first airflow speed, for example. Other embodiments may startin the last mode that the blower unit 100 was in when it was turned off.Other embodiments may start in the turbo mode. The mode in which theblower unit 100 starts may be set to different options for differentembodiments. Various embodiments may also allow the start mode to beselected by a user as part of a setup option.

Additionally, depending on the usage of the blower unit 100, the airflowmay be continuous at a minimum airflow speed to meet regulatoryrequirements. For example, presently, in the United States a respiratorshould have a minimum airflow speed of 170 L/min and 160 L/min in theEuropean Union.

At 504, the blower controller 110 checks to see if there is any inputfor the blower fan mode. For example, in an embodiment, a user can entervia the user interface 300 and/or 320 whether to use a normal (constantairflow speed) mode, an intermittent airflow speed mode, or a turbomode, and also to turn off the blower unit 100.

If the input indicates a normal mode, then at 506 the blower controller110 sets the blower fan 120 for normal mode. At 508, the blowercontroller 110 controls the blower fan 120 to blow at the constant firstairflow speed. Then the blower unit 100 may start the process again byrunning at the selected speed at 502. The first airflow speed may beadjustable in various embodiments of the disclosure.

If the input indicates a turbo mode, then at 510 the blower controller110 sets the blower fan 120 for turbo mode. At 512, the blowercontroller 110 controls the blower fan 120 to blow at the second airflowspeed for a period of time where the second airflow speed is greaterthan the first airflow speed. Then the blower unit 100 may start theprocess again by running the blower fan at the second airflow speed at502 for the period of time. After the period of time is up, the blowerfan 120 at the first airflow speed.

If the input indicates intermittent mode, then at 514 the blowercontroller 110 sets the blower fan 120 for intermittent mode. At 516,the blower controller 110 controls the blower fan 120 to blow at thefirst airflow speed for a first period of time, and at a second airflowspeed for a second period of time, where the second airflow speed isgreater than the first airflow speed. Then the blower unit 100 may startthe process again by running at the appropriate speed at 502.Accordingly, the blower fan 120 will blow air at the two differentspeeds until the blower unit 100 exits the intermittent mode.

The first period of time may be independent of the second period oftime. The airflow speeds and the periods of time for the various modesare dependent on the airflow speed pattern. The airflow speed patternmay be adjustable in various embodiments of the disclosure.

The periods of time for the first airflow speed and/or the secondairflow speed may be measured using any appropriate technology that maybe appropriate. For example, the time may be measured by software loops,or a timer in the hardware logic block 122 or 250 may be set and thetimer may be checked periodically or the timer may set an interrupt uponreaching the time it is set to count. A timer may also be available, forexample, in the blower controller 110 or another processor such as thecontroller 256.

If the input indicates that the blower unit 100 should be shut off, theblower unit 100 will enter shutdown mode at 518. The shutdown mode 518may include, for example, saving the present mode into memory 112 to usethe next time the blower unit 100 is turned on. At 520, an indication ofshutdown may be output to the user interface 114 and/or 244. Theindication may be flashing an LED, turning on an LED, or displaying amessage indicating shutdown, or some other appropriate indication. Thepower may be turned off at 522, and the flowchart is at an end stage at524.

Various embodiments disclose changing the airflow speed from a lowerspeed to a higher speed and vice versa. During the changing of thespeed, the rate of change of speed may be different when going from highspeed to low speed and when going from low speed to high speed. Forexample, when going from high speed to low speed, power to the blowerfan 120 can be reduced or removed to let the blower fan 120 slow down byitself. Going from low speed to high speed may use different amounts ofpower depending on the remaining capacity of the battery 130 and/orother parameters that may be used by the blower controller 110. However,the blower fan 120 may also use power to slow down the blower fan 120more quickly. Again, the amount of power used may be controlled by theblower controller 110. Accordingly, the rate of change for changing theairflow speed can be variable.

Again, while an example flow diagram has been described, variousembodiments need not be limited to this example. For example, the numberof airflow speeds and the switching from one airflow speed to anotherare implementation dependent.

The present methods and systems may be realized in hardware, software,and/or a combination of hardware and software. The present methodsand/or systems may be realized in a centralized fashion in at least onecomputing system, or in a distributed fashion where different elementsare spread across several interconnected computing systems. Any kind ofcomputing system or other apparatus adapted for carrying out the methodsdescribed herein is suited. A typical combination of hardware andsoftware may include a general-purpose computing system with a programor other code that, when being loaded and executed, controls thecomputing system such that it carries out the methods described herein.Another typical implementation may comprise one or more applicationspecific integrated circuit or chip. Some implementations may comprise anon-transitory machine-readable (e.g., computer readable) medium (e.g.,FLASH memory, optical disk, magnetic storage disk, or the like) havingstored thereon one or more lines of code executable by a machine,thereby causing the machine to perform processes as described herein. Asused herein, the term “non-transitory machine-readable medium” isdefined to include all types of machine readable storage media and toexclude propagating signals.

As utilized herein the terms “circuits” and “circuitry” refer tophysical electronic components (i.e. hardware) and any software and/orfirmware (“code”) which may configure the hardware, be executed by thehardware, and or otherwise be associated with the hardware. As usedherein, for example, a particular processor and memory may comprise afirst “circuit” when executing a first one or more lines of code and maycomprise a second “circuit” when executing a second one or more lines ofcode. As utilized herein, “and/or” means any one or more of the items inthe list joined by “and/or.” As an example, “x and/or y” means anyelement of the three-element set {(x), (y), (x,y)}. In other words, “xand/or y” means “one or both of x and y”. As another example, “x, y,and/or z” means any element of the seven-element set {(x), (y), (z),(x,y), (x,z), (y,z), (x,y,z)}. In other words, “x, y and/or z” means“one or more of x, y and z”. As utilized herein, the term “exemplary”means serving as a non-limiting example, instance, or illustration. Asutilized herein, the terms “e.g.” and “for example” set off lists of oneor more non-limiting examples, instances, or illustrations. As utilizedherein, circuitry is “operable” to perform a function whenever thecircuitry comprises the necessary hardware and code (if any isnecessary) to perform the function, regardless of whether performance ofthe function is disabled or not enabled (e.g., by a user-configurablesetting, factory trim, etc.).

The present methods and/or systems may be realized in hardware,software, or a combination of hardware and software. The present methodsand/or systems may be realized in a centralized fashion in at least onecomputing system or in a distributed fashion where different elementsare spread across several interconnected computing systems. Any kind ofcomputing system or other apparatus adapted for carrying out the methodsdescribed herein is suited. A typical combination of hardware andsoftware may be a general-purpose computing system with a program orother code that, when being loaded and executed, controls the computingsystem such that it carries out the methods described herein. Anothertypical implementation may comprise an application specific integratedcircuit or chip. Some implementations may comprise a non-transitorymachine-readable (e.g., computer readable) medium (e.g., FLASH drive,optical disk, magnetic storage disk, or the like) having stored thereonone or more lines of code executable by a machine, thereby causing themachine to perform processes as described herein.

While the present method and/or system has been described with referenceto certain implementations, it will be understood by those skilled inthe art that various changes may be made and equivalents may besubstituted without departing from the scope of the present methodand/or system. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the presentdisclosure without departing from its scope. Therefore, the presentmethod and/or system are not limited to the particular implementationsdisclosed. Instead, the present method and/or system will include allimplementations falling within the scope of the appended claims, bothliterally and under the doctrine of equivalents.

What is claimed:
 1. A respirator configured to provide air to aprotective device, comprising: a filter configured to filter the air; ablower fan configured to provide continuous air flow at variable speeds;an air duct configured to direct air from the blower fan to an exhaustlocation, the blower fan configured to blow air through the air duct;and a blower controller configured to: control the blower fan toautomatically adjust an airflow speed of the blower fan to a pluralityof airflow speeds over a plurality of different time periods, theplurality of airflow speeds being within an airflow speed range.
 2. Therespirator as defined in claim 1, further comprising at least one sensorconfigured to detect at least one environmental condition, the blowercontroller being configured to adjust the airflow speed in response tothe detected environmental condition.
 3. The respirator as defined inclaim 2, wherein the at least one sensor is a temperature sensor, theblower controller being configured to adjust the airflow speed accordingto the airflow speed pattern in response to at least one of: detectingthat ambient temperature around the respirator has exceeded atemperature threshold and detecting that ambient temperature in theprotective device has exceeded a temperature threshold.
 4. Therespirator as defined in claim 2, wherein the at least one sensor is anair quality sensor, the blower controller being configured to adjust theairflow speed according to the airflow speed pattern in response to atleast one of: detecting that air quality around the respirator hasfallen below a pre-determined air quality threshold and detecting thatair quality in the protective device has fallen below a pre-determinedair quality threshold.
 5. The respirator as defined in claim 2, furthercomprising a communication circuit configured to receive external sensorenvironmental information sensed by an external sensor device externalto the respirator, wherein the blower controller is configured to adjustthe airflow speed according to the airflow speed pattern in response tothe received external sensor environmental information.
 6. Therespirator as defined in claim 5, wherein the communication circuitreceives the external sensor environmental information wirelessly. 7.The respirator as defined in claim 1, wherein the airflow speed rangeincludes a lower airflow speed of at least 160 liters per minute.
 8. Therespirator as defined in claim 1, wherein the airflow speed rangeincludes a lower airflow speed of at least 170 liters per minute.
 9. Therespirator as defined in claim 1, further comprising a batteryconfigured to provide power to the respirator.
 10. The respirator asdefined in claim 1, wherein changing from a first airflow speed to asecond airflow speed is at a variable airflow change rate.
 11. Therespirator as defined in claim 1, further comprising a protective devicecoupled to the exhaust location of the air duct.
 12. The respirator asdefined in claim 11, wherein the respirator is configured to connect tothe protective device to provide the air to an interior of theprotective device.
 13. The respirator as defined in claim 11, whereinthe protective device is one of: a head worn device and a protectiveclothing.
 14. The respirator as defined in claim 1, further comprising auser interface device configured to receive an input from a user,wherein the blower controller is configured to use the input to controlthe blower fan to increase the airflow speed for a first period of timeto a first upper airflow speed.
 15. The respirator as defined in claim14, wherein the blower controller is configured to increase the firstperiod of time to a longer period with each successive input received bythe user interface device until a maximum period of time is reached,wherein a next input received by the user interface device decreases themaximum period of time to the first period of time.
 16. The respiratoras defined in claim 14, wherein the blower controller is configured toincrease the first upper airflow speed to a higher upper airflow speedwith each successive input received by the user interface device until amaximum upper airflow speed is reached, wherein a next input received bythe user interface device decreases the maximum upper airflow speed tothe first upper airflow speed.
 17. The respirator as defined in claim 1,wherein at least one of the plurality of airflow speeds is adjustable.18. The respirator as defined in claim 1, further comprising a userinterface device configured to receive an input from a user, wherein theblower controller is configured to use the input: to control the blowerfan to toggle between outputting varying air flow and outputting asubstantially constant air flow.